Amplifier



FIG. 1 is a front view of an amplifier showing my new design;

FIG. 2 is a rear view thereof;

FIG. 3 is a left side view thereof;

FIG. 4 is a right side view thereof;

FIG. 5 is a top view thereof; and,

FIG. 6 is a bottom view thereof.

The broken line showing of the amplifier is included for the purpose of illustrating portions of the amplifier and forms no part of the claimed design. 

CLAIM The ornamental design for an amplifier, as shown and described. 